[systemd-devel] Suppressing spam error messages in the system journal

[David C. Partridge]

Hi all,

system-resolved is spamming the system logs with thousands of messages:

	Server returned error NXDOMAIN, mitigating potential DNS violation
DVE-2018-0001, retrying transaction with reduced feature level UDP.

So I thought I'd come to the systemd list to see what can be done.

The system in question is a fresh installation of LUbuntu 20.04.1 and the
offending errors started appearing in bulk not long after I had installed
transmission-daemon and moved my existing configuration across.

I've added the following to etc/rsyslog.d/50-default.conf:

	if ($programname == "systemd-resolved") and ($msg contains
"DVE-2018-0001") then stop

which means that these messages no longer clog up syslog.

However this doesn't suppress them in the system journal.

Three questions spring to mind:

	1) Is there any way in journald.conf to perform a message
suppression similar to the one I used for syslog? If not should there be
one?

	2) Could resolved be changed so that this message is only emitted
(say) once for every 100 or 500 times that the condition is detected.

	3) Is there a problem in the way that transmission is using DNS
that's triggering this?

Thanks
David